textproduct: Albany

WHAT HAS CHANGED

No significant changes with this update.

KEY MESSAGES

1) Very cold temperatures for tonight, with low temperatures dropping as low as -10 to -18F across the southern Adirondacks, and single digits above/below zero elsewhere.

2) Moderate confidence for an initial period of snow on Tuesday that changes to rain and/or a wintry mix, especially near and south of I-90. There remains uncertainty regarding snowfall amounts and areal coverage of snow/wintry mix.

3) Moderate confidence for temperatures to trend warmer than normal for the end of the week into next weekend, especially in valley areas, which will likely ripen and partially melt the existing snow pack. With multiple opportunities for precipitation during this period, the combination of falling rain plus melting snow may start to break-up some existing river ice.

DISCUSSION

KEY MESSAGE 1...

Clear skies and decreasing wind tonight, along with a deep snowpack remaining in place will allow temps to drop off rapidly after sunset. Across portions of the southern Adirondacks, min temps as low as -15 to -18 F are expected by daybreak. Elsewhere, widespread low temps in the single digits below to above zero are expected. Winds will trend to nearly calm by daybreak, so wind chill ("feels-like") temps will be nearly the same as the actual temps around daybreak.

KEY MESSAGE 2...

Approaching wave of low pressure from the west along developing frontal boundary looks to bring a period of snow/wintry mix across the region Tuesday, favoring areas mainly south of I-90 late Tuesday morning through early afternoon, then expanding to areas near and north of I-90 during the afternoon. There remains some uncertainty in how much precipitation occurs farther north (north of I-90), as 13Z/Sun NBM shows greatest 24-hour chances for >0.50" QPF ending 7 AM Wed for areas south of I-90 (where chances are 30-60%), with chances north of I-90 generally less (20-40)%. Should the precipitation expand far enough north, with colder air in place, more precipitation would fall as either snow or a wintry mix (including some freezing rain), and would result in potentially hazardous travel conditions for the Tuesday evening commute for areas mainly north of I-90. Precipitation could linger into Tuesday night, some of which could remain as light snow or a wintry mix for areas north of I-90.

KEY MESSAGE 3...

Moderate confidence continues for above normal temperatures late this week into next weekend. However, confidence levels are lower across the southern Adirondacks, upper Hudson Valley and across southern VT, as a frontal boundary may tend to drop back southward and bringing slightly colder temps to portions of these areas, at least for Thursday through Friday night. As another wave of low pressure tracks along the frontal boundary, there could be a wintry mix on the north side of where the boundary sets up, which could include these aforementioned areas. 13Z/Sun NBM 24-hour probs for >.01" flat ice accretion ending 7 AM Saturday are 10-20%, greatest across southern VT, the northern Berkshires and higher terrain of Hamilton County in NY.

Farther south and west, confidence is higher for above normal temps. In fact, 13Z/Sun NBM 24-hour probs ending 7 PM Saturday for max temps >50F are 80-90%+ for Albany and areas south/west, and 60-80% in these same areas ending 7 PM Sunday. Probs are less to the north and east (10-30%), reflecting some uncertainty in ultimate placement of the frontal boundary and southern edge of cooler air. The warmer temperatures and resulting snowmelt would increase the potential for river rises and ice break up on rivers, especially areas south of I-90 for next weekend.

With the potential warming, there will also be several opportunities for precipitation, maximized across the SW Adirondacks which should be proximate to the aforementioned frontal boundary and passing waves of low pressure. 13Z/Sun NBM 48-hour QPF > 1" ending 7 AM Saturday is 30-50% across the southwest Adirondacks, northern Mohawk Valley extending into the Lake George/Saratoga region. Should warmer temperatures occur coincident with this rainfall, the combination of incoming rain and snow melt could provide the necessary mechanisms to at least start breaking up existing ice on rivers even in some northern and high terrain areas. We will continue to closely monitor temperature and precipitation trends for the end of this week into this weekend.

AVIATION /18Z SUNDAY THROUGH FRIDAY/

For the TAF period ending 18Z/Mon, mainly VFR conditions are expected despite occasional/patchy Cigs of 3500-4500 FT AGL this afternoon, and again between 08Z-14Z/Mon. There could be borderline MVFR Cigs at KPSF and also KALB later tonight, however overall chances are too low to include mention in TAFs at this time. Winds will be north to northeast at 8-12 KT with some gusts up to 20-25 KT this afternoon, then will back into the north to northwest and decrease to 5-10 KT after sunset, becoming light/variable by daybreak. Light/variable winds will trend into the west/northwest and increase to 5-10 KT by late Monday morning.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.